To protect the head of an individual conducting welding operations, a helmet is usually employed. Such helmets typically include a rigid shell adapted to, at least, partially enclose the head of a wearer to defend it from incandescent matter ejected from a welding area. A darkened window in the front surface of the shell permits the wearer to observe the welding area while shielding the eyes from the high-intensity light emitted by a welding heat source such as an electric arc or acetylene torch flame. As air circulation through most welding helmets is limited, excessive perspiration and rapid fatigue can occur as the helmet wearer's head and body are warmed by energy radiated from the welding heat source.
Welding helmets have been proposed which provide automatic ventilation to a wearer through the use of a fan powered by photovoltaic or solar cells. Unfortunately, the proposed helmets are relatively complex, expensive and difficult to manufacture. Further, such helmets have heretofore included only a single, planar, solar cell panel on the exterior surface thereof for receiving light from a source like an electric arc or gas flame.
In order to power the fan, a wearer of one of the previously proposed helmets is required to continuously maintain his or her head in a fixed orientation wherein the single solar cell panel more-or-less directly faces the light source. In the frequent situations where the head of a wearer must turn away from the light source, ventilation provided by the fan is undesirably reduced or abated altogether. There remains a need, then, for a welder's helmet which may be automatically ventilated by initiation of a light source, such as an electric arc, and which will remain consistently ventilated when the head of the helmet wearer is turned to the left or right relative to the light source.